Practice, not loss of sight, improves sense of touch in the blind: study

May 11, 2011, McMaster University
A photo of the device used in the fingertips experiments

New research from McMaster University may answer a controversial question: do the blind have a better sense of touch because the brain compensates for vision loss or because of heavy reliance on their fingertips?

The study, published in the most recent edition of the , suggests daily dependence on touch is the answer.

Twenty-eight profoundly blind participants—with varying degrees of Braille expertise—and 55 normally sighted adults were tested for touch sensitivity on six fingers and both sides of the lower lip.

Researchers reasoned that, if daily dependence on touch improves tactile sensitivity, then blind participants would outperform the sighted on all fingers, and blind Braille readers would show particular sensitivity on their reading fingers. But if alone improves tactile sensitivity, then blind participants would outperform the sighted on all body areas, even those that blind and sighted people use equally often, such as the lips.

"There have always been these two competing ideas about why blind people have a better sense of touch," explains Daniel Goldreich, corresponding author and a professor in the Department of Psychology, Neuroscience & Behaviour. "We found that dependence on touch is a driving force here. Proficient Braille readers—those who might spend hours a day reading with their —performed remarkably better. But blind and sighted participants performed equally when the lips were tested for sensitivity."

Researchers used a specially-designed machine which held the pad of the participant's fingertip perfectly still for the experiments. While the finger lay over a hole in the table, the machine pushed rods with textured surfaces through the opening until they met the fingertip. Researchers asked subjects to identify the patterns by touch. A similar test was performed on the lower lip.

Not only did blind participants do better than their sighted peers, but Braille readers, when tested on their readings hands, outperformed nonreaders who were also blind. For Braille-reading participants, their reading fingers were more sensitive than their non-reading fingers.

"These results may help us design further experiments to determine how to improve the , which could have applications later in life," says Mike Wong, study author and a graduate student in the McMaster Integrative Neuroscience Discovery & Study program. "Braille is extraordinarily difficult to master, particularly as an adult. In future we may find new ways to teach to people who have recently become blind."

More information: A pdf of the study can be found at: dailynews.mcmaster.ca/images/Blindnesstouch.pdf

Related Stories

Recommended for you

Finding unravels nature of cognitive inflexibility in fragile X syndrome

January 22, 2018
Mice with the genetic defect that causes fragile X syndrome (FXS) learn and remember normally, but show an inability to learn new information that contradicts what they initially learned, shows a new study by a team of neuroscientists. ...

Epilepsy linked to brain volume and thickness differences

January 22, 2018
Epilepsy is associated with thickness and volume differences in the grey matter of several brain regions, according to new research led by UCL and the Keck School of Medicine of USC.

Research reveals atomic-level changes in ALS-linked protein

January 18, 2018
For the first time, researchers have described atom-by-atom changes in a family of proteins linked to amyotrophic lateral sclerosis (ALS), a group of brain disorders known as frontotemporal dementia and degenerative diseases ...

Fragile X finding shows normal neurons that interact poorly

January 18, 2018
Neurons in mice afflicted with the genetic defect that causes Fragile X syndrome (FXS) appear similar to those in healthy mice, but these neurons fail to interact normally, resulting in the long-known cognitive impairments, ...

How your brain remembers what you had for dinner last night

January 17, 2018
Confirming earlier computational models, researchers at University of California San Diego and UC San Diego School of Medicine, with colleagues in Arizona and Louisiana, report that episodic memories are encoded in the hippocampus ...

Recording a thought's fleeting trip through the brain

January 17, 2018
University of California, Berkeley neuroscientists have tracked the progress of a thought through the brain, showing clearly how the prefrontal cortex at the front of the brain coordinates activity to help us act in response ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

klawy
4 / 5 (1) May 11, 2011
Anybody that is suprised? The brain can never just compensate - you have to learn and learn through practice. Can't realy belive that someone puts money and effort in to this - it might sound logic at a first glance. Turn it the other way around does your vision improve because you loose your sense of feeling... Why not blindfold people for 8h a day and see if there sense of touch is improved... Seriously... Do we need to test that hypothesis too?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.